Semiconductor integrated circuits such as semiconductor memory devices include an input circuit that receives an input signal at certain timing. The input circuit generally receives an input signal according to the timing when the logic of a strobe signal changes.
In a conventional semiconductor memory device such as a NAND-cell type flash memory, an interface of single-data rate (SDR) having a rate of about 40 Mbps is adopted. In recent years, it is required that an interface adopt an double-data rate (DDR), and that the DDR interface have a rate of 133 Mbps-200 Mbps or even higher speed to improve access efficiency of the NAND-cell type flash memory.